g thanks for the post! Lockpicking is in fact a system that was never developed as we might have taken it. There are only a few reasons to invest in Lockpicking Talent (range, less AP) but they are very minimal and hard to justify.
Considering the game has over 170 dungeons and many thousands of treasure chests, it is not something we are planning to go back and address in a title that is 4+ years old.
Locked chests and boss (red) chests prevent you from easily snagging and using the loot during the battle you are in.